The present invention provides a novel phosphatidic acid phosphatase gene. Theobject of the present invention can be solved by providing a nucleotidesequence set forth inSEQ ID NO: 1 or SEQ ID NO: 7, SEQ ID NO: 4 or SEQ ID NO: 9, or SEQ ID NO: 5 orSEQID NO: 10; and an amino acid sequence set forth in SEQ ID NO: 2 or SEQ ID NO:6.